Investigating the Dynamic Tensile Response of Lean Duplex Stainless Steel and the Effects of Radial Waves Using the Recovered Plat-Impact Experiment.

Lean Duplex Stainless Steel 2404 (LDX2404) is the newest commercial type of duplex stainless steels, recently introduced by Outokumpu®. This paper investigates the dynamic tensile failure (spall strength) of this new alloy under different peak stresses (4.5 GPa to 8.2 GPa) via the recovered plate-impact experiment using a single stage gas gun. The microstructural investigation for the as-received and soft recovered post-shock material conditions were accomplished using Electron Backscatter Diffraction (EBSD) and optical microscopy. The effect of the radial release waves and the effectiveness of using momentum trap rings on the spall strength and the spall damage during the impact experiment were studied. Results indicate that LDX2404 experienced spall damage for the entire range of tested peak stresses. The spall strength was not affected by the implementation of momentum trapping rings whereas; the damage content was highly influenced. The spall damage of LDX 2404 exists parallel to the phase boundary interfaces, which are normal to the impact direction. Grain orientation, based on Taylor factor values, was not controlling the voids nucleation and voids growth. [ABSTRACT FROM AUTHOR]